I have an (intuitive?) aversion against the fashionable 'symbolic' policies such as sending a Patriot battery to Turkey, Israel, wherever - or a company/battalion to the Baltic region. This goes beyond my more specific aversion and criticism of tripwire forces or considerations about the stupidity of multinational formations.
The fashion is going wild these days, so it's overdue to look at it with more clarity and less of a tunnel vision. I will ignore the "We're doing something, stop bugger us" and the "politicians playing with their toys" aspects of such minimal deployments in this blog post.
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I see two different kinds of deterrence that matter in this context:
(1) Political action as deterrence
This is what politicians feel competent at. Political deterrence rests on the assumption that political resolve to defend is the big lever to maintain peace.
This is actually somewhat founded in history. Back in 1939 Hitler dared to attack Poland (already, instead of later) because he did not believe the French or British would declare war on Germany for it. He was half-right only; the French and British did not declare war on the Soviet Union for the exact same offence a few days later.
The link that failed in the chain that was tasked to preserve the peace was thus the persuasiveness of French and British top politicians, who had indeed changed their course from appeasement to an arms racing final spurt (if not war preparations) but a few months earlier.
The symbolic policies may be interpreted as efforts to be persuasive enough; politicians playing their game instead of delegating deterrence. It takes Russian creativity to see an invasion threat in four patchwork battalions, so one can semi-plausibly claim that such minimal and symbolic deployments are non-aggressive. It's also more civilised than "strong man" speeches and mannerisms.
They're also rather cheap and can thus be agreed-on by a few top politicians on the fly.
(2) Military ability as deterrence
What would happen if politicians are persuasive in their resolve to defend, but their stick is little and brittle? Such as an army that cannot deploy in force and in time to matter, and has but two days worth of ammunition only and hardly any reserve personnel pool anyway?
This is where military deterrence steps in:
A military that was defined, funded and built well may - if not kept too secret - convince a potential aggressor that an aggression would enter a land of suffering and embarrassments beginning on day two. Reserves would be large enough to not only keep this up unbearably long, but the defending alliance would also have the resources to escalate into entirely different theatres of war, potentially ruining the aggressors 'achievements' and influence in altogether different countries.
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I suppose that in much of Europe - Germany (and actually Russia) included - politicians favour their own game greatly over doing the political oversight required to 'get the military right' for deterrence and defence. They favour not only intervention games, but whenever there's an opportunity they prefer the political game of minimal deployments instead of having much interest in the adequacy of the stick as a whole.
There are more obvious motivations driving the nonsense (and I hinted at them above), but the key appears to be that most politicians in NATO Europe and especially Germany have lived through times of peace in Europe and their withered repertoire for deterrence simply doesn't come close to the potential because they stick to a small and predictable tool set.
Thus we deter aggression with a huge, inefficient bulk of forces and flimsy tripwire forces instead of with an efficient, purpose-oriented and elegant force AND top politicians who are persuasive in communicating that forceful instant defence in the event of aggression would be self-evident.
I am most likely naturally pre-disposed to their way of deterrence because I am too much under influence of having read too much about history.